US8248281B2 - High speed, high resolution, high precision voltage source/AWG system for ATE - Google Patents
High speed, high resolution, high precision voltage source/AWG system for ATE Download PDFInfo
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- US8248281B2 US8248281B2 US13/011,786 US201113011786A US8248281B2 US 8248281 B2 US8248281 B2 US 8248281B2 US 201113011786 A US201113011786 A US 201113011786A US 8248281 B2 US8248281 B2 US 8248281B2
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- 230000009977 dual effect Effects 0.000 claims abstract description 16
- 101100458289 Drosophila melanogaster msps gene Proteins 0.000 claims description 7
- 238000012360 testing method Methods 0.000 description 12
- 238000010586 diagram Methods 0.000 description 8
- 101100015484 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) GPA1 gene Proteins 0.000 description 5
- 230000006870 function Effects 0.000 description 4
- 101100067427 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) FUS3 gene Proteins 0.000 description 3
- 238000013500 data storage Methods 0.000 description 2
- 229920005994 diacetyl cellulose Polymers 0.000 description 2
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Classifications
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/10—Calibration or testing
- H03M1/1009—Calibration
- H03M1/1028—Calibration at two points of the transfer characteristic, i.e. by adjusting two reference values, e.g. offset and gain error
Definitions
- the invention relates to automatic test equipment (ATE) for testing integrated circuits.
- DAC digital-to-analog converters
- ILE integrated linearity error
- a general purpose of the present invention is to provide an ATE, solving at least one of the above mentioned issues.
- the problem is solved by the present invention by a method for use in an ATE for compensating a linearity error of a dual digital-to-analog converter.
- the method comprises a step of receiving a digital data signal, where said digital data signal comprises a plurality of bits.
- the digital data signal indicates a voltage signal to be generated.
- Said plurality of bits represents a set of consecutive bits being confined within a highest bit and a lowest bit.
- a high-bit-array is applied to a first digital-to-analog converter.
- Said high-bit-array is composed of a consecutive sub-set of the plurality of bits of the digital data signal. The sub-set includes the highest bit of the digital data signal.
- the method comprises a further step of using at least a part of a correction data of a look-up-table for manipulating at least a part of a low-bit-array.
- the low-bit-array is composed of a consecutive sub-set of the plurality of bits of the digital data signal.
- the sub-set includes the lowest bit of the digital data signal.
- the manipulation of the at least a part of the low-bit-array comprises a step of multiplying the at least a part of a low-bit-array by at least a first part of a correction data of the look-up-table, thereby providing a first result.
- the manipulation of the at least a part of the low-bit-array comprises a further step of adding at least a part of the achieved first result and at least a second part of the correction data of the look-up-table, thereby providing a second result.
- Said second result is applied to a second digital-to-analog converter.
- the method comprises a step of the first digital-to-analog converter and the second digital-to-analog converter converting their respective received digital data into a first analog signal and a second analog signal.
- the method comprises a step of the high-bit-array and the low-bit-array sharing at least one common bits of the digital data signal.
- the method comprises a step of the look-up-table being composed of at least two sub-look-up-tables, wherein the first part of the correction data being provided by a first sub-look-up-table of the at least two sub-look-up-tables, and the second part of the correction data being provided by a second sub-look-up-table of the at least two sub-look-up-tables.
- the method comprises a step of adding the first analog signal and the second analog signal, thereby providing a third result, and converting the third result into an analog voltage signal.
- the method comprises a step of determining the converted analog voltage signal.
- the present invention provides an apparatus for compensating a linearity error of a dual digital-to-analog converter, comprising means for compensating a linearity error of a dual digital-to-analog converter adapted to operate according to any of the above mentioned embodiments.
- the apparatus for compensating a linearity error of a dual digital-to-analog converter comprises a first digital-to-analog converter and a second digital-to-analog converter.
- the apparatus for compensating a linearity error of a dual digital-to-analog converter comprises said first digital-to-analog converter and said second digital-to-analog converter when in operation each providing at least 50 Msps.
- the apparatus for compensating a linearity error of a dual digital-to-analog converter comprises said first digital-to-analog converter and said second digital-to-analog converter are having each a parallel input, whereby an input to a digital-to-analog converter may be a one or more bit input.
- the apparatus for compensating a linearity error of a dual digital-to-analog converter comprises said first digital-to-analog converter and said second digital-to-analog converter are arranged on the same die.
- FIG. 1 schematically illustrates a simplified diagram showing a configuration of an ATE according to the invention
- FIG. 2 schematically illustrates a simplified block diagram showing a configuration of an ATE according to the invention
- FIG. 3 schematically illustrates a coarse DAC and a fine DAC program bit relation
- FIG. 4 schematically illustrates a calibrated and an uncalibrated status of a Main DAC linearity error
- FIG. 5 schematically illustrates a DAC calibration error curve
- FIG. 6 schematically illustrates a DAC calibration error correction.
- a “condition where a member A is connected to a member B” refers to the condition where the member A and the member B are physically connected to each other directly and to the condition where the member A and the member B are connected indirectly via other members that do not affect the electrical connection.
- a “condition where a member C is provided between the member A and the member B” refers to, in addition to the condition where the member A and the member C or the member B and the member C are connected to one another directly, the condition where the members are connected indirectly via other members that do not affect the electrical connection.
- ATE automatic test equipment
- FIG. 1 schematically illustrates a simplified diagram showing a configuration of an ATE according to an embodiment of the invention. It illustrates receiving a digital data signal 1000 , comprising a plurality of bits, the digital data signal 1000 indicating a voltage signal to be generated, said plurality of bits representing a set of consecutive bits being confined within a highest bit and a lowest bit.
- FIG. 1 illustrates using at least a part of a correction data 4100 of a look-up-table 4000 for manipulating 5000 at least a part of a low-bit-array 1200 , being composed of a consecutive sub-set of the plurality of bits of the digital data signal 1000 , the sub-set including the lowest bit of the digital data signal 1000 , wherein the manipulation 5000 of the at least a part of the low-bit-array 1200 comprises the steps of multiplying the at least a part of a low-bit-array 1200 by at least a first part 4110 of a correction data 4100 of the look-up-table 4000 , thereby providing a first result 1300 , adding at least a part of the achieved first result 1300 and at least a second part 4120 of the correction data 4100 of the look-up-table 4000 , thereby providing a second result 1400 , and applying the second result 1400 to a second digital-to-analog converter 2200 .
- FIG. 2 schematically illustrates a simplified block diagram showing a configuration of an ATE according to another embodiment of the invention.
- This embodiment comprises a dual current DAC 2100 , 2200 which has primary coarse DAC 2100 having the coarse current output and the secondary DAC 2200 with current divider 3210 which extends the resolution and corrects the primary DAC linearity error.
- a digital circuit contains automatic linearity correction circuit.
- the upper bits 1100 are connected to primary DAC 2100 and connected to LUT (look up table) 4000 to apply correction data (gain and offset) 4110 , 4120 to lower bits 1200 .
- the lower bits 1200 are applied to gain multiplier 5100 and the offset adder 5200 to correct the primary DAC 2100 error.
- the calibration circuit 7000 consists from reference DAC 7200 , differential amplifier 7100 and the precision ADC 7300 enables precision calibration without external calibration circuit.
- the calibration circuit measures the output voltage of the amplifier and determines the output of the amplifier.
- the DVM digital voltmeter
- the invention may use a dual current output DAC on one single chip (one chip dual current DAC) 2100 , 2200 so that both DAC 2100 , 2200 chip temperatures are nearly identical and are having nearly identical reference input, as well as nearly identical current set, thus enabling good matching and tracking.
- said first digital-to-analog converter 2100 and said second digital-to-analog converter 2100 used in the apparatus are arranged on the same die 2000 .
- FIG. 2 also shows the first digital-to-analog converter 2100 and the second digital-to-analog converter 2200 converting their respective received digital data into a first analog signal 3100 and a second analog signal 3200 .
- FIG. 2 also adding the first analog signal 3100 and the second analog signal 3200 , thereby providing a third result 1500 , and converting the third result 1500 into an analog voltage signal 3300 , can be seen.
- the converted analog voltage signal 3300 can be determined.
- the primary DAC 2100 output 3100 is connected to amplifier directory and the secondary DAC 2200 output is connected to amplifier 6000 via current divider 3210 .
- the current divider 3210 ratio is 1/256 in this case.
- Voltage reference 8100 may be used in DAC to specify the output ranges. In case of current output DAC, full scale (or maximum) current is determined by the voltage reference 8100 with current set resistor Rset. Also the offset current 8200 may be determined by the voltage reference circuit 8000 .
- the output range of the DAC may be unipolar or bipolar. In a preferred embodiment the output range of some DAC outputs is unipolar and offers an output range of 0 mA to 10 mA. Usual ATE is required to have bipolar output voltage (e.g. ⁇ 50 V to +50 V).
- the output amplifier 6000 works as current to voltage converter. To have bipolar operation, an offset current 8200 is required. In the diagram case, an offset current of ⁇ 5 mA is applied and the amplifier 6000 has a ⁇ 5 mA to +5 mA current range with a DAC output current of 0 mA to 10 mA. Then current will be converted to appropriate bipolar voltage.
- the main DAC controls the power amplifier output voltage (feedthrough voltage). For example it may require a 100 Msps class low latency DAC to keep its function and phase margin.
- the amplifier may have seamless change of its output voltage without gain selection. Further, in this way the glitch can be reduced when the voltage range is changed.
- the circuit illustrated in FIG. 2 may correspond to this requirement.
- the concept of this circuit is to make use of at least two DACs 2100 , 2200 as a coarse DAC 2100 and a fine DAC 2200 , respectively.
- the coarse DAC 2100 offers a large step size and the fine DAC 2200 interpolates the coarse DAC's 2100 step.
- An apparatus for compensating a linearity error of a dual digital-to-analog converter may comprise a compensating section for compensating a linearity error of a dual digital-to-analog converter adapted to operate according to one or more embodiments of the invention.
- the apparatus comprises a first digital-to-analog converter 2100 and a second digital-to-analog converter 2200 .
- said first digital-to-analog converter 2100 and said second digital-to-analog converter 2200 used in the apparatus—when in operation— may provide at least 50 Msps, more preferably between 50 Msps to 150 Msps, most preferable 100 Msps.
- said first digital-to-analog converter 2100 and said second digital-to-analog converter 2200 used in the apparatus each have a parallel input, whereby an input to a digital-to-analog converter may be a one or more bit input, preferable a 2 bits to 22 bits input, more preferable a 10 bits to 16 bits input, most preferable a 14 bit input.
- FIG. 3 schematically illustrates a coarse DAC 2100 and a fine DAC 2200 program bit relation.
- Both bit-arrays consist of active bits AB and “don't-care” bits DCB.
- the DAC 1 2100 active LSB 2110 and DAC 2 2200 MSB (most significant bit) 2210 are overlapped.
- This concept of using at least two DACs 2100 , 2200 benefits from calibration to compensate DAC 1 2100 LSB 2110 DNL error (differential non-linear error).
- At least two LUT (Look Up Table) 4000 are prepared to compensate DAC 1 2100 DNL and also DAC 2 2200 gain.
- the high-bit array 1100 and the low-bit array 1200 share at least one common bit of the digital data signal 1000 .
- the look-up table 4000 may also be composed of at least two sub-look-up tables 4000 ′, 4000 ′′, wherein the first part 4110 of the correction data 4100 is provided by a first sub-look-up table 4000 ′ of the at least two sub-look-up tables 4000 ′, 4000 ′′, and the second part 4120 of the correction data 4100 is provided by a second sub-look-up table 4000 ′′ of the at least two sub-look-up tables 4000 ′, 4000 ′′.
- FIG. 4 schematically illustrates a calibrated and an uncalibrated status of a main DAC 2100 linearity error.
- the first line UCL reflects the linearity error of the primary DAC 2100 . This error can be corrected by adding the negative offset to secondary DAC 2200 to cancel the error.
- the second line CL reflects the error after calibration. In this case, resolution is extended to more than 18 bits.
- the linearity error of the secondary DAC 2200 is also 1/256.
- the error of the secondary DAC ( 2200 ) is nearly without influence (typically less than 20 bits resolution) for the result.
- FIG. 5 schematically illustrates a DAC calibration error curve over time 9600 and output voltage 9700 . It illustrates an ideal correction line 9000 and a stepwise calibration of the error curve 9100 .
- each step comprises the secondary's DAC 2200 step value 9200 , step value error 9300 and step error correction value 9400 , thus receiving a corrected error curve 9500 .
- the calibration circuit measures the output voltage of the amplifier for each voltage step of the coarse DAC.
- the linearity error is calculated for each voltage step.
- the offset and gain for the fine DAC 2100 is calculated to correct the linearity error of the fine DAC 2100 .
- FIG. 6 schematically illustrates a DAC calibration error correction. It illustrates a calibration error correction of a coarse DAC 2100 , and a calibration of a fine DAC 2200 . Furthermore it illustrates the sum of both DAC signal in uncalibrated 9100 and calibrated 9500 state.
- program storage devices e.g., digital data storage media, which are machine or computer readable and encode machine-executable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of said above-described methods.
- the program storage devices may be, e.g. digital memories, magnetic storage media such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media.
- the embodiments are also intended to cover computers programmed to perform said steps of the above-described methods.
- processors may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software.
- the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared.
- explicit use of the term “processor” or “controller” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, network processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), read only memory (ROM) for storing software, random access memory (RAM), and non volatile storage.
- DSP digital signal processor
- ASIC application specific integrated circuit
- FPGA field programmable gate array
- ROM read only memory
- RAM random access memory
- any switches shown in the FIGS. are conceptual only. Their function may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the implementer as more specifically understood from the context.
- any block diagrams herein represent conceptual views of illustrative circuitry embodying the principles of the invention.
- any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.
Abstract
Description
I Total =I DAC1+1/256I DAC2.
Required bit@40 V−>(+40 V−(−40 V))/0.00006103515625 V=2949120=220.3
In this
Claims (11)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
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US13/011,786 US8248281B2 (en) | 2011-01-21 | 2011-01-21 | High speed, high resolution, high precision voltage source/AWG system for ATE |
JP2011288943A JP2012156995A (en) | 2011-01-21 | 2011-12-28 | High-speed, high-resolution and highly accurate voltage source/awg system for ate |
DE102012100474A DE102012100474A1 (en) | 2011-01-21 | 2012-01-20 | HIGH-RESOLUTION, HIGH PRECISION HIGH-SPEED VOLTAGE SOURCES / AWG SYSTEM FOR AN ATE SYSTEM |
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US13/011,786 US8248281B2 (en) | 2011-01-21 | 2011-01-21 | High speed, high resolution, high precision voltage source/AWG system for ATE |
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US20120188108A1 US20120188108A1 (en) | 2012-07-26 |
US8248281B2 true US8248281B2 (en) | 2012-08-21 |
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US13/011,786 Active US8248281B2 (en) | 2011-01-21 | 2011-01-21 | High speed, high resolution, high precision voltage source/AWG system for ATE |
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US (1) | US8248281B2 (en) |
JP (1) | JP2012156995A (en) |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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US9344104B1 (en) * | 2013-05-18 | 2016-05-17 | S9Estre, Llc | Digital to analog converter and analog to digital converter calibration techniques |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
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US5585802A (en) * | 1994-11-02 | 1996-12-17 | Advanced Micro Devices, Inc. | Multi-stage digital to analog conversion circuit and method |
US6580177B1 (en) * | 1999-06-01 | 2003-06-17 | Continuum Control Corporation | Electrical power extraction from mechanical disturbances |
US20080042048A1 (en) * | 2005-09-26 | 2008-02-21 | Sony Corporation | Digital-to-analog converter, analog-to-digital converter, and semiconductor device |
US20090121907A1 (en) * | 2007-11-08 | 2009-05-14 | Advantest Corporation | D-a convert apparatus and a-d convert apparatus |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0258926A (en) * | 1988-08-24 | 1990-02-28 | Nec Ic Microcomput Syst Ltd | D/a converter |
JP2674332B2 (en) * | 1991-03-08 | 1997-11-12 | 日本電気株式会社 | Series-parallel type analog / digital converter |
JPH07177037A (en) * | 1992-03-31 | 1995-07-14 | Yokogawa Electric Corp | D/a converter |
JP4097796B2 (en) * | 1998-08-21 | 2008-06-11 | 株式会社アドバンテスト | DA converter and successive approximation AD converter using the DA converter |
US7068193B2 (en) * | 2002-09-26 | 2006-06-27 | Analog Devices, Inc. | Integrated digital calibration circuit and digital to analog converter (DAC) |
JP4047342B2 (en) * | 2005-03-29 | 2008-02-13 | 株式会社アドバネット | Data processing device |
-
2011
- 2011-01-21 US US13/011,786 patent/US8248281B2/en active Active
- 2011-12-28 JP JP2011288943A patent/JP2012156995A/en active Pending
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- 2012-01-20 DE DE102012100474A patent/DE102012100474A1/en not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5585802A (en) * | 1994-11-02 | 1996-12-17 | Advanced Micro Devices, Inc. | Multi-stage digital to analog conversion circuit and method |
US6580177B1 (en) * | 1999-06-01 | 2003-06-17 | Continuum Control Corporation | Electrical power extraction from mechanical disturbances |
US20080042048A1 (en) * | 2005-09-26 | 2008-02-21 | Sony Corporation | Digital-to-analog converter, analog-to-digital converter, and semiconductor device |
US20110205097A1 (en) * | 2005-09-26 | 2011-08-25 | Sony Corporation | Digital-to-analog converter, analog-to-digital converter, and semiconductor device |
US20090121907A1 (en) * | 2007-11-08 | 2009-05-14 | Advantest Corporation | D-a convert apparatus and a-d convert apparatus |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9344104B1 (en) * | 2013-05-18 | 2016-05-17 | S9Estre, Llc | Digital to analog converter and analog to digital converter calibration techniques |
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DE102012100474A1 (en) | 2012-07-26 |
JP2012156995A (en) | 2012-08-16 |
US20120188108A1 (en) | 2012-07-26 |
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